Suction cup bumper



INVENTOR. Everett E.Shorpe ATTORNEYS.

United States Pate t 2,990,991 SUCTION CUP BUMPER Everett 'E. Sharpe, Shelton, 'Conn., assignor to Better Packages, Incorporated, a corporation of New York Filed May 25, 1959, Ser. No. 815,672

3 Claims. (Cl. 226-137) This invention relates to a bumper or cushioning device for stopping the movement of a rapidly movable or reciprocating element. It is particularly applicable to use in connection with a movable machine element which makes repeated reciprocations at varying rates of speed and whichhas to be brought to a stop. without unnecessary shock, without bounce, and in a definite position. The invention may be utilized under various conditions where it is desirable to meet the above requirements. As an example of a use where the invention has proved particularly advantageous, the invention is illustrated and described inthe present application as applied to a machine for dispensing selected, measured lengths of tape or strip.

In a tape dispenser of the character mentioned, means are provided for feeding a tape in pieces of varying length, as determined by the operator. Such machines involve tape feeding instrumentalities often operated by reciprocating levers or the like, and also include measuring instrumentalities having reciprocating measuring and resetting elements. Every time a strip of tape is dispensed, one or more of these reciprocating elements is moved through a path the length of which depends on the length of tape fed, and is then instantly returned to initial position by means such as a spring. It is important to stop the reciprocating member in its exact initial position so that it will be ready to function accurately at the next operation of the machine; and it is also important to stop the reciprocating member as far as possible without shock and noise and without bounce, which might result in inaccuracies of measuring or feeding.

In accordance with the present invention, bumper means are utilized involving a suction cup which strikes a complementary member so as to cushion the impact both by the resilience of the material of which the cup is formed and by the action of the air cushion trapped within the cup. The cup, on striking the abutment member, expels part of the air in the chamber so that the cup will adhere by suction to the abutment. Means are provided to permit limited leakage into the cup so that immediately after the movement of the reciprocating member has been arrested, and bounce prevented by the suction in the cup, air will leak into the cup so as to break the suction, thereby releasing the suction effect after the period of possible bounce has passed, and permitting immediate free movement of the cup away from the abutment for the ensuing operation of the device. Obviously the cup may be mounted on a reciprocating part to cooperate with the fixed abutment, or the cup may be mounted in fixed position and engaged by a movable abutment.

In the accompanying drawings illustrating certain preferred embodiments of the invention:

FIGURE 1 is a side elevation of a tape dispensing machine partly broken away showing the bumper construction of the present invention applied thereto;

FIG. 2 is a fragmentary longitudinal sectional view of the vacuum cup bumper construction shown in FIG. 1;

FIG. 3 is a perspective view of another form of tape dispensing machine showing the invention applied thereto;

FIG. 4 is a fragmentary sectional view showing the bumper cup construction of 'FIG. 3.

Referring to the drawings in detail, the bumper comprises a vacuum cup formed of resilient material such as natural or synthetic rubber which has a hollow 12 therein surrounded by a resilient rim 14. The vacuum cup cooperates with an abutment 16. In the construction illustrated in FIGS. 1 and 2, the abutment 16 is mounted on the stationary frame of the machine and the cup is attached to a bracket 18 on a reciprocating sector 20. Means are provided for permitting a limited leakage into the cup either through a hole in the cup wall, or, as illustrated in FIGURES 1 and 2, through a very small notch or groove 22 formed in the surface of the abutment 16. FIGURES 1 and 2 show the sector 20 in its terminal position with the cup in engagement with the abutment, and position of the sector and cup when moved away from the abutment being indicated in dotted lines. When the sector moves to the full line position, the cup strikes sharply against the abutment and is slightly compressed, thereby acting as a cushion, this action being supplemented by the compression of the air within the cup. At the same time a slight amount of air is expelled so that the cup tends to adhere momentarily to the abut ment. This resists any tendency of the cup to bounce away from the abutment. However, almost instantly enough air leaks into the cup to break the vacuum, thereby permitting the cup to assume its normal shape and locating the sector in the exact initial position ready for the next stroke. Also, the release of the suction which occurs almost instantly after the moment of impact when bounce could occur, avoids any possibility of the cup tending to cling to the abutment and interfere with the free motion of the reciprocating member away from the abutment on the next operation of the device.

The particular example of the invention illustrated in FIGS. 1 and 2 shows diagrammatically a measuring tape dispensing machine of the type more fully illustrated in an application for patent filed by Theodore H. Krueger March 25, 1959, Serial No. 801,867. In this machine, tape is fed from a tape roll 30 between a pair of tape feeding rollers 32 and 34 and over a moistening brush 36. The rolls are driven by a motor, not shown, and the length of feed is controlled by a series of switches and push buttons, also not shown. The switches are reset by a resetting roller 38 carried by the sector 20 on which the suction cup 10 is mounted. When the type is fed by the rolls the sector is driven in a counter clockwise direction by a large gear 40 driven by a pinion 42 which rotates with the roll 32. During the period of tape feeding, the sector is moved by means of a tooth 44 which engages one of the teeth of the gear 40, it being driven into engagement with the gear by means "of a solenoid clutch 46. When a desired length of tape has been fed, the feed rolls are stopped and simultaneously the solenoid clutch 46 releases the tooth 44 and the sector returns to its initial position under the influence of a clock type spring 48. With this construction it will be seen that at every operation of the machine the sector is moved away from the abutment for a greater or lesser distance, depending upon the length of tape to be fed at that particular operation; and as soon as the desired length has been fed, the sector snaps back to its original position where it is stopped accurately by the engagement of the suction cup with the abutment, bounce being prevented as described above.

FIGS. 3 and 4 show the application of the novel bumper to another type of tape feeding machine in which the tape is fed by tape rolls (not shown) driven by means of a hand crank or lever 50 mounted on the side of the machine. After each feeding operation the hand crank is returned to its initial position in a well understood manner by a suitable spring on the interior of the machine, and its motion is stopped by means of a suction cup bumper 10a similar to that already described, which is mounted on the frame of the machine and is engaged by an abutment face 16a mounted on the crank. in this in- 3, stance the suction cup is shown as havinga small leakage hole 52 in the wall thereof in lieu of the groove 22 in the abutment plate, as shown inFIGS. l and 2.

While I have illustrated andrwdese'ribedin detailcertain 1. A- tape dispenser having means for feeding variable:

lengths of tape and having a reciprocatingelement associated with the tape feeding means movable through diff ferent distances from a zero position dependingfupon the length of tape fed, means for returning the'reciprocating element to zero position after each tape feeding opera- 4 tion, and means for stopping the reciprocating element in accurate zero position without rebound comprising a vacuum cup element and a cooperative abutment element, one of which is mounted on the reciprocating element and one of which is mounted in a relatively fixed position. 2. A construction as claimed in claim 1, in which means are provided permitting leakage into the interior of'the References Cited in the file of this. patent UNITED STATESPATENTS 1,827,745 Hagemann Oct. 20, 1931 Birr Mar. 12, 1940" 

